Cylinder head (camshaft) covers for the M103 and various other M-B motors have a tendency to "deteriorate" over time - the black paint separates from the cover and flakes off, both on the inside and the outside of the cover. Additionally, the cover itself frequently undergoes a sort of deterioration, whereby localized areas of deformation and surface defects appear. When probed, these regions of deformation typically reveal either a small amount of dry powdery material or slurry of the same material.

Could someone shed some light on the composition (powdered metal?) and manufacturing process (baked?) of these covers, as well as the reason for their deterioration? Is the shedding of paint flakes ( from the interior aspect of the cover) into the engine oil cause for concern?

This problem is not unique to M-B; I have observed BMWs and Jaguars with identical symptoms.

As far as I know, The valve cover on my 190E is made of Magnesium, and most other mb's as well (correct me if I am not). Why Mg? Because of its excellent heat transfer properties. Now this means that the paint used on the cover is toast over a period of time since Mg passes heat onto the pain!!. I tried painting my flaky vavle cover with some high temp paint....result: It was good for the firt two weeks, and after that the color faded. and now its just pure ugly! I will have a professional powder coat it for me and hopefully it will stay that way!